Q. The first cutting of my haylage crop never seems to turn out right. What could be going wrong?
A. Haylage is unique in that it is harvested more than once and each cutting provides slightly different challenges. Haylages have a higher level of buffering (higher resistance to pH drop) coupled with lower levels of fermentable sugars and lactic acid producing bacteria (LAB) than corn crops for silage. Plant sugar levels can be especially low if the haylage crop is harvested in cloudy or overcast conditions. All of these factors combine to make it more difficult to achieve the fast fermentation and fast pH drop required to maximize digestible nutrient recovery and prevent bad fermentations.
Compounding these issues, haylage crops can also contain high (greater than 10 percent DM) ash levels, due to soil being picked up as the crop is close to the ground and raked after cutting. Soil can carry very high levels of spoilage bacteria (e.g. clostridia), introducing a potentially large load of contaminants into the crop. It is also important that slurry applications are fully washed in, as residual slurry can provide a hefty load of enterobacteria (gut micro-organisms, e.g. E. coli).
Typically, the first cutting represents about 30 to 40 percent of the total season DM yield. Neutral detergent fiber digestibility (NDF-D) is often higher than any other cutting of the season, and alfalfa quality declines fastest for first cutting if there are any harvest delays. Timing is everything for maximum forage quality, especially with the first cutting of alfalfa. I would recommend making sure you optimize your harvest timing as a first step, and also make sure that you time slurry applications well. At cutting, avoid shaving the fields and do not over-rake the crop.
It is important to use an inoculant containing homolactic LAB proven to dominate the ensiling fermentation, such as Pediococcus pentosaceus 12455, coupled with enzymes to generate sugars and drive the fermentation. Make sure that you get all other management parameters optimized – chop length, packing, fast fill, cover and seal, and feedout management – and you should be on the right path to high quality first cuttings!